Embodiments of the present invention relate to video conferencing and, more specifically, to correlating remote viewing and local video capture.
Video conferencing and video telephone applications have been advancing with great speed in the past several years. With the increase in global business, it has become increasingly more difficult to engage in face to face meetings with business contacts, clients, and the like. In some measure, the use of the telephone and electronic mail (E-mail) communication has served to cover the gap. However, face to face meetings can still convey more information about the participants than E-mail and telephonic communications. Because of the desire to engage in face to face meetings with contacts, video conferencing has become increasingly more popular.
Video conferencing requires apparatus at each location of the conference to allow the participants to have video captured and transmitted to the other location for viewing. The quality of video transmitted and viewed depends on a number of factors, including the size of the picture a viewer sees, and the frame rate of the transmission. A lower frame rate results in more flicker and non-fluid movements. A smaller picture size makes it more difficult to see images and details of images. Frame rates and video size depend on the expected bandwidth of the transmission, the processing speed of any processor processing the transmitted video, and the capabilities of the capture and display devices.
Often, remote viewing devices and local video capture devices have different specifications and capabilities, and cannot necessarily display the same capture video size. Even if the same capture video size is available, the frame rate for one of the devices may be far lower than the expected frame rate in the application. Such video capture mismatches lead to problems with transmissions that must be dealt with to ensure quality video communication. When video capture devices differ, and video size or frame rates do not match between two end points, it is time consuming and frustrating to attempt to match capabilities.
One method of matching capabilities is to stretch the video image at one of the video conference locations. That is, if a back-end viewing device cannot provide an adequate frame rate for a certain video size, the size is reduced at the back-end, and transmitted to the front-end at the smaller size. The video is then stretched at the front-end video device, allowing display of the video at the desired size and frame rate, but with a reduced quality picture. In other words, the image size at the front-end viewing device is increased from its transmitted size, which is smaller than the desired remote video size.
In many instances, the viewer of the remote viewing device video will determine the capture video size of the front-end or local device, and the wire video size for transmission of video between the two devices. It would be desirable to improve the selection of video sizes to increase the quality of remote video. It would a similarly be desirable to select capture video size and wire video size taking into account the capabilities of the local video viewing device.
In one embodiment, a method for choosing the wire video size of a video telephony product includes deriving a wire video size from a desired remote video size of a remote viewing device, and choosing a remote viewing target frame rate. A determination is made as to whether the chosen wire video size has a capture frame rate less than a threshold percentage of a maximum frame rate of the remote viewing device and a capture video size less than a threshold percentage of a maximum stretch of the wire video size. If the capture frame rate or capture video size are less than the threshold percentage of the maximum frame rate or the threshold percentage of the maximum stretch of the wire video size, a smaller wire video size is selected, and choosing a target frame rate through determining if a smaller wire video size is selected are repeated.
In another embodiment, a video conferencing station includes a host video conferencing device having a video capture device, a transmission device for transmitting video, and a central processing unit. A computer readable medium capable of execution by the central processing unit causes the central processing unit to execute a method as described above. Other methods may also be executed.
Other embodiments are described and claimed.